Extraction or coagulation of india-rubber from the latex.



No Drawing.

UNITED STATES PATENT OFFICE.

SAMUEL CLELAND DAVIDSON, OE BELFAST, IRELAND.

' EXTRACTION on. COAGULATION or INDIA-RUBBER FROM THE LATEX.

'certain new and useful Improvements in and Relating to the Extraction or Coagulation of India-Rubber from the Latex, of which the following is a specification.

My invention relatesto the extraction or coagulation of india rubber from the'latex obtained from rubber trees, and more particularly from the variety known as Para or Heoea Brasz'lz'ensz's and its object is to enable a product to be obtained which will have creosote or carbolic acid or alike phenoloidbody, uniformly and perfectly distributed throughout its mass, thus ,securmg 111 a greater degree than hitherto the preservative and strengthening efiectsof the creosote, carbolic acid or the like upon the rubber. In some cases formaldehydev may also be incorporated with the rubber by the process. My invention is applicable to said latex while it is in the fluid'condition in which it is collected from the rubber trees, and whether or not it has been subjected to previous treatment, such, for e'xample, as when ammonia or other alkali or alkahne substance is added to the latex during or soon after its collection from the rubber trees to preventa tendency which sometimes exists to spontaneous coagulation before the latex can be brought into the factory, or,

when the latex, in order to preserve and re tain-it in a fluid condition 'is treatedwith formaldehyde or other suitable antiseptic having no coagulating action on the rubber when added to the latex. 7

According to one method of carryin'g'my invention into effect, Ifirstly add to said fluid latex an alkaline and aqueous solution of a mixture consisting of creosote or carbolic acid, oran admixture thereof (hereinafter referred to as creo oarbolic) with a suflicient quantity of caustic alkali, such asvcaustic soda or potash, or an alkaline substance, such as biborate of soda, or any admixture of said substances, whereby said alkaline compound, or compounds of creosote or car- 'bolic acid, or creo carbolic is 'or' are ren- Specification of Letters Patent. Patented 1111376, 1915. Application filed January 28, 1913. Serial No: 744,732. H

of'the alkaline phenoloid body are for example one part of creosote or creo-carbolio and two or more partsof an aqueous solut1on of caustic soda or caustic potash of-a strength of 50 Twaddcll. If formaldehyde is added it may be employed in a proportlon of one part. of formaldehyde of 40% strength to each four or moreparts of alkalized creosote or phenoloida The pro- 1porttions may however be varied within. wide For brevity of description, said alkaline compounds of creosote, or carbolic, or creocarbolic asv the case may be are hereinafter referred to as alkalized.creoecarbolic, it belng understood that where alkalized creocarbolic is mentioned, alkalized carbolic alone, or creosote alone are included in the term. c

When applying any of the above'described preparations-of alkalized creo-ca rbolic, a dilute aqueous solution thereof may for example be prepared in the ratio of one part of the mixture to about 20vor more parts of water, and a suflicient quantity thereof is added to the fluid latex to render 1t slightly alkaline, but exact proportions cannot accurately be defined byweight or measurement, owing to the fact that the latex from diiferentlocalities often varies at difierent seasons, and morning and eveningtappingsalso frequently vary in characterlstics, and consequently involve variations in the treatment, but I find that effectiveresults are usually obtained by adding the dilute aqueous solution of the selected mixture in just suflicient quantity to impart to the latex a slight'alkaline reaction to test paper. 1

After the latex has been treated as above described, coagulation of the rubber therefrom is efi'ecteda's in the'already customary lute solution of the alkalized creo-carbolic,

for the first treatment of the latex, may be heated, or the latex may be heated before, after, or during the first treatment, and the water for making the dilute solution ofacid for the second, or coagulating treatment may also, if desired be heated.

When coagulation of 1 he rubber has been completely effected,it may be removed from ing, and may be pressed into thin cakes, and

dried in any of the ordinarily employed rubber drying apparatus, or, if finished 1n the form of thin sheets or bands, its drying can be efiected by hanging same on poles in an airy room or shed, and, when sufficiently dried, it may be pressed in molds into blocks, or otherwise suitably prepared for transmission to the market.

I wish it to be understood that in the preparation of the alkalized creo-carbolic as herein described I do not limit myself to the particular alkalis or alkaline substance named, and further-that for the second, or coagulating treatment of the latex, I do not limit myself to the employment of the partioular acids referred to, as any acid or acid substance having a suitable neutralizing action on the alkalinity of the alkalized creo-carbolic of the first treatment of the latex, and a coagulating effect on the rubber may be employed.

In the ordinary smoking of rubber-it is true that a certain amount of phenoloid bodies are introduced by the smoke in combination with pyroligneous and other acids,

and concurrently with its introduction c0- agulation of the rubber from the latex ocours but by treating the latex with an alkaline solution of the phenoloid body or bodies according to the present invention same mixes intimately-with the fluid latex and without causing any coagulation of the rubber therefrom until the latex is treated with an acid or acid substance whereupon the rubberwhich coagulates out therefrom is evenly impregnatedwith creosote,'carbolic, or creocarbolic as the case may be.

What I claim and desire to secure by Letters Patent is I 1. In a process for the treatment of india rubber latex, adding to the liquid latex a dilute alkaline solution of a phenoloid body as a preparatory treatment thereof, prior to coagulation of the contained rubber therefrom. p I

2. In a process for the treatment of india rubber latex, adding to the liquid latex a dilute alkaline solution of a phenoloid body and formaldehyde asa preparatory treatment thereof prior to coagulation of the contained rubber therefrom.

3.A process for extracting india rubber from latex, comprising adding to the liquid 6. In a process for the treatment of india rubber latex, addin to the liquid latex a dilute alkaline solution of creosote and formaldehyde as a preparatory treatment thereof prior to coagulation of the contained rubber therefrom.

7. A process for extracting india rubber from latex, comprising addingto the liquid latex a dilute alkaline solution of creosote,

and coagulating the rubber contained in the latex by a dilute acid solution.

8. A process for extracting india rubber from latex, comprising adding to the liquid latex a dilute alkaline solution of creosote and carbolic acid, and coagulating the rubber contained in the latex by an acid solution.

9. In a process for the treatment of india rubber latex, adding to the liquid latex a dilute alkaline creo-carbolic solution as a preparatory treatment thereof prior to coagulation of the contained rubber there from.

10. In a process for the treatment of india rubber latex, adding to the liquid latex a dilute alkaline creo-carbolic solution and formaldehyde. as a preparatory treatment thereof prior to the coagulation of the contained rubber therefrom.

11. A process for extracting india rubber from latex, comprising adding to the liquid latex a dilute aqueous alkalized creo-carbolic solution and coagulating the rubber contained in the latex by a dilute solution of 'an acid substance, substantially as described.

12. A process for extracting india rubber from latex, comprising adding to the liquid latex a dilute aqueous alkalized creo-carbolic solution and formaldehyde, and coagulating the rubber contained in the latex by a dilute solution of an acid substance, substantially as described.

13. Process for extracting india rubber from latex, comprising adding to the liquid latex a dilute aqueous creo-carbolic solution alkalized by biborate of soda, and coagulat ing the rubber contained in the latex by a dilute acid solution, substantially as described.

14'. In a process for extracting india rubber from latex, adding to the liquid latex 1,146,852 i i a 8' an alkaline solution-of a phenoloid body as phenoloid contained in solution therein, by a preparatory treatment thereof, priorto coaddition of an acid substance applied for agulation of the contained rubber therefrom. coagulating the india rubber from the latex. v i 15. A process for extracting india rubber In witness whereof, I have hereunto 15. i from latex, comprising addingto the liquid signed my name in the presence of two sublatex an dalkaline solutio? if a gllgenoloid scribing witnesses. body, an coagu ating o t e ru er contained in the latex by an acid substance. SAMUEL CLELAND DAVIDSON?" 16. A' process for extracting indiarubber Witnesses: 10 from latex, comprising liberating in the JOHN J oHNsoN,

. rubber latex a phenoloid from an alkalized HUGH TAYLOR CoULTER. 

